The disclosure relates generally to the cleaning of a photoconductive member of an electrophotographic machine. More particularly, the disclosure relates to a cleaning blade maintenance process and system that calculates the amount of toner mass at a toner cleaner blade, and applies a corrective procedure, such as insertion of a paperless copy into the print job, to replenish the toner mass at the cleaner blade, reducing cleaning failure by maintaining a toner level to give adequate lubrication and also by inhibiting migration of debris, such as paper fibres, to the blade tip.
In a typical electrophotographic printing process, a photoconductive member is charged to a substantially uniform potential so as to sensitize the surface thereof. The charged portion of the photoconductive member is exposed to a light image of an original document being reproduced. Exposure of the charged photoconductive member selectively dissipates the charges thereon in the irradiated areas. This records an electrostatic latent image on the photoconductive member corresponding to the informational areas contained within the original document. After the electrostatic latent image is recorded on the photoconductive member, the latent image is developed by bringing a developer material into contact therewith. Generally, the developer material comprises toner particles adhering triboelectrically to carrier granules. Toner particles attracted from the carrier granules to the latent image form a toner powder image on the photoconductive member. The toner powder image is then transferred from the photoconductive member to a copy sheet. Heating of the toner particles permanently affixes the powder image to the copy sheet. After each transfer process, the toner remaining on the photoconductor is cleaned by a cleaning device.
One type of cleaning device is a urethane blade that is configured in either a wiper or doctor mode to remove residual toner and other particles. In some instances a disturber brush is used in combination with the blade to remove paper debris and to disturb the residual toner image. It is known that the residual toner acts as a lubricant for the cleaner blade and helps to minimize blade tuck, which can lead to streaking of the image or can cause blade and/or photoreceptor damage. One way of replacing lost blade lubrication is to place a toner swath across a photoreceptor at some known interval to assure blade lubrication.
U.S. Pat. No. 6,438,329 to Budnik et al., commonly assigned to Xerox Corporation and incorporated herein by reference in its entirety, provides a customer replaceable unit (CRU) having a cleaning blade lubrication system. Upon initial usage of the CRU, a toner patch is developed without being transferred to deposit an initial layer of toner on the cleaning blade for lubrication. No replenishment is provided.
U.S. Pat. No. 5,463,455 to Pozniakas et al., commonly assigned to Xerox Corporation and incorporated herein by reference in its entirety, provides an adaptive cleaning blade lubrication system for electrophotographic printing machines that calculates the density of each transferred image and deposits a band of toner in an interdocument gap that lubricates the cleaner blade across its width.
U.S. Pat. No. 5,349,429 to Jugle et al., commonly assigned to Xerox Corporation and herein incorporated by reference in its entirety, provides a cleaner blade lubrication system that continuously provides lubrication to the cleaning blade through use of a downstream foam lubricating roll that uses waste toner cleaned from the imaging surface to continuously lubricate the cleaning blade.